1. Field of the Invention
The present invention relates to a vehicle behavior control device allowing each of a plurality of vehicle behavior controls, such as braking force control or front-rear driving force distribution control, to be performed efficiently and stably in a vehicle with the plurality of vehicle behavior control.
2. Description of the Prior Art
Recently, with regard to vehicles, various vehicle behavior control techniques, including traction control, braking force control and front-rear driving force distribution control, have been proposed and put into practical use. When these various vehicle behavior controls are used in one vehicle, these controls preferably operate without interfering with each other or conflicting with each other.
For example, Japanese Patent Laid-Open No. 2003-191774 discloses an integrated vehicle motion control device in which the software configuration of a device controlling in an integrated manner a plurality of actuators for executing plural kinds of motion controls in a vehicle is hierarchized so as to include: a command unit determining a target vehicle state quantity based on driving related information; and an execution unit receiving the determined target vehicle state quantity as an command from the command unit and executing the received command via at least one of the plurality of actuators. In the integrated vehicle motion control device, the command unit includes: a high command unit configured to determine a first target vehicle state quantity based on the driving related information without considering dynamic behavior of the vehicle; and a low command unit configured to determine a second target vehicle state quantity in view of the dynamic behavior of the vehicle based on the first target vehicle state quantity received from the high command unit.
In the above described integrated vehicle motion control device technique disclosed in Japanese Patent Laid-Open No. 2003-191774, however, when an abnormality occurs due to some reason in the command unit, particularly in the high command unit, it is possible that subsequent commands are not properly executed and no actuator can operate properly, thus deteriorating the basic performance of the vehicle.
In view of the above circumstances, the present invention has been devised, and has an object of providing a vehicle behavior control device which can normally allow a plurality of vehicle behavior controls to operate efficiently and in an integrated manner and even when an abnormality occurs in this integrating control section, allows each of the vehicle behavior controls to operate while maintaining the basic performance.